Telegraphic receiving system.



J. M. FELL. TELEGRAPHIC RECEI VING SYSTEM.

APPLICATION FILED JULY 8,19l6.

Patented N 0V. 6, 1917.

Jbhh M Fe// I Arty.

UNITED STATES PATENT ()FFICE.-

JOHN M. FELL, 0F HAGKENSA C K, NEW JERSEY, ASSIGNOR TO AMERICANTELEPHONE AND TELEGRAPH COMPANY, A CORPORATION OF NEW YORK.

'rnweaarnrc nncmvme sr'srum.

Specification of Letters Patent.

PatentedNov. 6, 1917.

To all *whom it may concern:

Be it known that I, JOHN M. FELL residing at Hackensack, in the countyof lZergen and State of New Jersey, have invented certain Improvementsin Telegraphic Receiving Systems, of which the following is aspecification.

This invention relates to telegraph systems and especially to means forreceiving signals. Its principal objects are to provide an organizationin which-the time of travel of the armatures of the receivin apparatusbetween their contact stops w1l be reduced and the firmness of contactwith the engaged stops increased, thus improving the quality of thesignals.

One arrangement for carrying out the mvention is illustrateddiagrammatically in the accompanying drawing.

My invention will be described in connection with a polarized relayadapted for use in a differential duplex telegraph system, the moreessential portlons of this apparatus being indicated at R. It is to beunderstood, however, that other t pes and forms of relay may beemployed. he' main windings 10 carried by cores 11 are shown asconnected in an operating circuit, of whi h 12 may be the main conductorleading to a distant station, 13 that of the artificial line of a duplexsystem, and 14 the common conductor connected to the contact of a polechanger, this artificial line, pole changer and relay being at thereceiving station and arranged in the usual manner. The relay magnetsare preferably polarized by a winding 15 upon a core 16 and suppliedwith current from a battery 17 The armature 18 of the relay,

playing between contacts 19 and 20, is joined through a relatively highresistance 21 with the grounded winding of a signal receiving apparatusR, which may be a polarized sounder. The contacts 19 and 20 are unitedto grounded batteries '23 and 23, respectively. Upon the cores 11 is anauxiliary winding 24 independent of the main and polarizing windings.One terminal of this auxiliary winding is joined to the relay armature,while the other terminal is connected to ground'through a resistance 25and condenser 26, and preferably through the winding of sounder R.v

Such'a signaling current arriving over the line that the armature 18 ismoved against the stop 19,. the condenser 26 is charged from battery23,, causing an impulse to flow from said battery through resistance 27,contact 19, armature 18, conductor 28, auxiliaryf winding 24, conductor29, resistance 25, condenser 26 and the winding of sounder R. Theauxiliary winding is so connected that the impulse, continuing until thecondenser is fully charged, acts to hold the armature v against thecontact while the operating current is building up toward its maximum.The magnetization thus imparted to the cores 11, 11 resists the tendencyof the armature to chatter upon the contact and thereby produce falsesignals, a condition often caused by induced or earth currents. Whenupon a reversal of the linecurrent the armature 18 leaves contact19, thecondenserdis: charges through the winding 24 and sounder R, giving animpulse opposite to that occurring when the condenser was charged. Theeffect of the magnetization of the cores 11, 11 is now such as to aidthe operating current to move'the armature, this coming at a time whensaid current is weakest. Upon reaching the contact 20 battery 23!charges the condenser through resistance 30, contact 20 and the pathfirst traced, with a succeeding discharge, resulting in a similarretaining and accelerating actionof the auxiliary circuit upon thearmature as that just described. By varying the capacity of thecondenser 26 and the magnitude of the ,resistance 25, the value ofcurrent in the auxiliary winding may be changed to control its efiect. Asuitable resistance has been found in practice to be 8000 ohms, whilethe capacity of theecondenser' maybe 2 microfara-ds. A resistance ofabout ten thousand ohms may be used at'21.

It should be further noted that as the charge and discharge of thecondenser passes through the windmg of the sounder R,

which constitutes. another element of the'resaid circuit beingcontrolled by the receiv- Q R I I neeasee in'g apparatus, and means forcausing a eeto contacts of the relay, means for deliver rent impulsethrough the receivingapparain an energizing pulse tothe relay upon tusand said device when the continuity of initiai change of engagementbetweengits the last-named circuitis altered. a armature and a contact,andital receiving 2. In a telegraphreceiving systern, an opapparatusincluded. in. the pat of said en: 35

10 second-named winding, a signal-receiving 'gizing circ 't for therelay independent 01? crating circuit, a relay having a mam windergizingmfulse. r ing and an auxiliary windlng, the main 5. egraph receivingsystem, an opwinding being connected in the operati'n crating circuitconnecting stations, a relay circuit, an auxiliary circuit including saihaving its-winding in said circuit, an enerdevice and a source ofcurrent controlled iby. the operating circ 't including a con contactsof the relay, and means fordehv- 1 denser, and a signal receivingapparatus i n erin a current impulse to the auxiliary eluded infidenergizing circuit,

win ing upon initial change of engagement [6; In a telegraph reeeivm'gsy in a S.

ls'between the relay armature and a contact. 'erat circuit, a relayhavin main win 3. In a telegraph receiving system, an opin andf anauxiliary Winn themain crating circuit, a-relay having a main windwingbeing-connected in t e operating ing and an auxiliary winding, the main,,circuit,'.anenergizing circuit for'the relay. winding being connectedin t e operating including a source Qoffcurrenhacontact of 2c circuit,and an energizing circuit for the the relaycits auxiliary windingandacon 5 relay including; asource of current,- a con- 1 denser, and asounder having its windingv a included-in said energizing circuit.

tact of the relay, its auxiliary winding a c condenser for delivering acurrent imnuije in testony whereof, ,li havesigried my a to saidauxiliary winding upon initiai change name tothis specification in thepresence of 25 of engagement between the relay armature two subscribingwitnesses, this'first day of 55.

and a contact, and a signal-receiving device July, 1921.6. controlled bysaid relay. c

JQHN it. t an Y tin a telegraph reeeivingsyste, anopQ Witnesses: rerating circuit, a relay having its winding Enwr F. Werson,

so in said circuit, a source. of current connected B; l men Hermann.

